RESUMO
Citizen science is an excellent tool in studies of the spatial distribution of non-native species. In Brazil, Opsanus beta has recently been introduced. Studies indicate the occurrence of this species in five estuaries off the Brazilian coast (Guanabara Bay, Sepetiba Bay, Santos Bay, Paranaguá Estuarine Complex and Guaratuba Bay). The present study aims to understand the dispersion of this species on the Brazilian coast through citizen science. Between January and May 2021, information about O. beta was weekly posted in 32 recreational fishing Facebook groups. Sixty-five fishers reported catches of O. beta in estuaries (Guanabara Bay, Sepetiba Bay, Santos Bay and Paranaguá Estuarine Complex). In addition, there were reports from other shallow areas outside adjacent estuaries (Bertioga and Peruíbe, in Sao Paulo State) and the first occurrence record for Laguna (Santa Catarina State), a southern estuarine zone (28° 29' 45â³ S to 48° 45' 36â³ W). In four estuaries along the Brazilian coast where O. beta was recorded, there are internal ports that trade with countries from the Gulf of Mexico and Caribbean Sea (species original range), indicating ballast water as a possible introduction route. In Laguna, the introduction may have occurred by maritime cabotage services. The reproductive capacity, the aquarists' interest, the absence of introduction policies aimed at this species and the cabotage fleet transportation may be factors that help further extend the dispersal of O. beta on the Brazilian coast.
Assuntos
Batracoidiformes , Ciência do Cidadão , Animais , Brasil , Região do Caribe , Monitoramento Ambiental , Estuários , HumanosRESUMO
Genypterus brasiliensis, a demersal fish of large size (1.3 m of total length), occurs in the southwest Atlantic (23 to 38oS) and well appreciated due to the quality of its flesh. It was analyzed through longline and trawl fisheries, and the average length and weight of 724 specimens were significantly different between them, with the biggest and heaviest specimens caught by the former. The weight-length relationships were significantly different based upon sex: females Wt=4x10-7Lt3.3799; r2=0.97; n=262; p<0.001, and males: Wt=4x10-7Lt3.3886; r2=0.95; n=190; p<0.001. Using the otoliths readings for 153 specimens (APE of 2% and CV of 4.2%), the growth parameters estimates reveal statistical differences between sexes (p=0.05; r2=0.889). The fisheries were composed of individuals aged 1 to 13 (females) and 1 to 14 years old (males), with ring formation in late spring. The back calculated parameters (VBGF) were: Loo=1,452.38 mm, K=0.0996, t0=-0.2757 yr-1 (females) and Loo=983.07 mm, K=0.155, t0=-0.236 yr-1 (males), and longevity as 29.8 and 19.1 years old, respectively. The low biological production allied to the slow growth and a late complete maturation and its endemism, allow classify G. brasiliensis as a vulnerable resource, jeopardizing a sustainable fishery. Until reliable quantitative biological data are available, precautionary management must be considered.
Assuntos
Pesqueiros/estatística & dados numéricos , Peixes/crescimento & desenvolvimento , Características de História de Vida , Animais , Oceano Atlântico , Peso Corporal/fisiologia , Brasil , Feminino , Longevidade , Masculino , Membrana dos Otólitos/crescimento & desenvolvimento , Dinâmica Populacional , Caracteres SexuaisRESUMO
The present study reports the occurrence of the bearded brotula, Brotula barbata, in four different localities off southern Brazil. These records extend the species' known distribution limit southwards, beyond Rio de Janeiro, to the state of Rio Grande do Sul (30° 50' S). Morphometric and meristic data for the specimens reported herein are provided and discussed.
Assuntos
Distribuição Animal , Peixes/anatomia & histologia , Animais , Oceano Atlântico , BrasilRESUMO
The concentrations of metals in tissues of Callinectes danae were evaluated, aiming to determine the bioaccumulation process of this species. Gills presented the highest mean concentrations for most metals, except for Hg (Assuntos
Braquiúros/metabolismo
, Monitoramento Ambiental
, Metais/metabolismo
, Poluentes Químicos da Água/metabolismo
, Animais
, Brasil
, Feminino
, Água Doce/química
, Masculino
, Metais/análise
, Água do Mar/química
, Poluentes Químicos da Água/análise
, Poluição Química da Água/estatística & dados numéricos
RESUMO
This study determined the concentrations of eleven metals in the blue crab, Callinectes danae, from nine sites in the Santos Estuarine System of Sao Paulo State, Brazil. The results were compared to guidelines established in the United States, Europe and Brazil for the safety of human consumers. Muscles of blue crabs were removed by dissection and concentrations of Al, Cd, Co, Cr, Cu, Fe, Hg, Mn Ni, Pb and Zn were determined. In general, the concentrations of metals were low, and the crabs were regarded as safe for human consumption. Crabs from a single site (site 4) exceeded the guidelines established by the United States and Europe, but not Brazil, for Pb, with a mean tissue concentration of 1.725 µg g(-1). With the exception of Al, Fe and Ni, significant differences were noted between sites in the concentrations of each metal in crab tissue.